Online retail giant Amazon began offering game downloads on Tuesday, opening an online store featuring more than 600 titles.

Amazon said all of the casual games available at its new Game Downloads Store at amazon.com/gamedownloads were priced below 10 dollars.

The games, which are available for a free 30-minute trial, are only playable on personal computers which run Microsoft's Windows.

Amazon is one of the largest online sellers of digital music and books and the Games Downloads Store is its first venture into the world of downloadable gaming.

Amazon purchased casual game maker Reflexive Entertainment in October.